ANC05LA027 · Cessna U206

The commercial pilot was on a personal flight with his immediate family, returning to his home/business on the shore of a remote lake adjacent to an airport. He had received forecast and current weather reports indicating an approaching cold/occluded front and deteriorating VFR weather conditions. The pilot transited a mountain pass into an area of rapidly deteriorating weather surrounding the destination lake. He reported that he elected to fly along the north shore of the frozen, snow-covered lake in moderate falling and blowing snow in visibility he estimated as about 1 mile, at an altitude of approximately 400 feet . He said that he thought he saw the south shoreline, close to his destination, and initiated a left turn toward the shoreline and over the lake. He indicated that once he was over the snow-covered white lake, with the white falling snow and overcast sky, he lost sight of the shoreline and turned to the right to return to the north shore. During the turn, he lost depth perception, descended, and collided with the lake, about 6 miles north-northeast of the destination airport. The airplane sank almost immediately, and the pilot said he had to cut his seatbelt to get out. He said he was unable to rescue any of his 3 passengers, his juvenile daughters, before the airplane sank in about 800 feet of water. The pilot's wife was also able to get out of the airplane, and they both hiked to a remote, unoccupied cabin to await rescue. The reported weather at the destination airport, approximately 37 minutes after the accident, was: Wind, 320 at 12 knots; visibility, one-half mile in heavy snow; sky, vertical visibility 200 feet, ceiling indefinite. The elevation of Lake Clark is approximately 260 feet msl.

Verbatim NTSB analysis and probable cause from the NTSB dataset